The instructions and explanation for this are well laid out, easy to follow and fun. Kids are always excited at the introduction of fire in an experiment. I think it is important to let students know that the cloud is not simply residual smoke, rather the smoke's presence helps give the vapor something to cling to and hang in the air. It is mentioned in the site, but younger students may miss this and not fully understand the experiment. Overall this activity does well to illustrate the basics of cloud formation on a smaller visibly available scale.